Reference: Salesforce Marketing Cloud Documentation on Journey Builder Exit Criteria

To run a journey multiple times a day based on newly compiled data, the marketer should set up an automation to populate the Entry Source Data Extension. This ensures that the latest data is always available to trigger the journey. The automation can be scheduled to run at the desired frequency, ensuring the journey starts with the updated data. Salesforce Marketing Cloud documentation on Automation Studio and Journey Builder entry sources provides detailed instructions on setting up and managing such workflows.

Interactive Email Forms might not be fully supported in all email clients, including Gmail. To ensure a better user experience, the email developer should configure fallback content for Gmail. This ensures that if the interactive form cannot be displayed, an alternative static content is shown instead, maintaining the email's functionality and message.
References:
* Salesforce Marketing Cloud Documentation: Interactive Email Forms

The Auto Suppression List in SFMC is used to automatically suppress subscribers who meet certain criteria, including those with a status of 'Held'. When a subscriber is marked as 'Held', it means that the system has detected delivery issues with that email address, such as a hard bounce. This can cause the subscriber key to appear twice in the _subscribers data view, once with the status 'Active' and once with 'Held'.
References: Salesforce Marketing Cloud Documentation on Auto Suppression Lists

In Salesforce Marketing Cloud, once an email is approved using Content Builder Approvals, any subsequent changes require the approval to be withdrawn first. This ensures that any modifications are tracked and re-approved if necessary. By withdrawing the email approval, you can make the necessary changes and then resubmit the email for approval. Reference: Salesforce Marketing Cloud Documentation on Content Builder Approvals.